linux-toradex.git/drivers/iio/adc, branch v4.20-rc6

Merge tag 'staging-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

2018-10-29T17:38:10+00:00

Pull staging/IIO driver updates from Greg KH:
 "Here is the big staging and IIO driver pull request for 4.20-rc1.

  There are lots of things here, we ended up adding more lines than
  removing, thanks to a large influx of Comedi National Instrument
  device support. Someday soon we need to get comedi out of staging...

  Other than the comedi drivers, the "big" things here are:

   - new iio drivers

   - delete dgnc driver (no one used it and no one had the hardware
     anymore)

   - vbox driver updates and fixes

   - erofs fixes

   - tons and tons of tiny checkpatch fixes for almost all staging
     drivers

  All of these have been in linux-next, with the last few happening a
  bit "late" due to them getting stuck on my laptop during travel to the
  Mantainers summit"

* tag 'staging-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (690 commits)
  staging: gasket: Fix sparse "incorrect type in assignment" warnings.
  staging: gasket: remove debug logs for callback invocation
  staging: gasket: remove debug logs in page table mapping calls
  staging: rtl8188eu: core: Use sizeof(*p) instead of sizeof(struct P) for memory allocation
  staging: ks7010: Remove extra blank line
  staging: gasket: Remove extra blank line
  staging: media: davinci_vpfe: Fix spelling mistake in enum
  staging: speakup: Add a pair of braces
  staging: wlan-ng: Replace long int with long
  staging: MAINTAINERS: remove obsolete IPX staging directory
  staging: MAINTAINERS: remove NCP filesystem entry
  staging: rtl8188eu: cleanup comparsions to false
  staging: gasket: Update device virtual address comment
  staging: gasket: sysfs: fix attribute release comment
  staging: gasket: apex: fix sysfs_show
  staging: gasket: page_table: simplify gasket_components_to_dev_address
  staging: gasket: page_table: fix comment in components_to_dev_address
  staging: gasket: page table: fixup error path allocating coherent mem
  staging: gasket: page_table: rearrange gasket_page_table_entry
  staging: gasket: page_table: remove unnecessary PTE status set to free
  ...

iio: adc: ti_am335x_adc: Disable ADC during suspend unconditionally

2018-10-09T10:28:26+00:00

Parent MFD device takes care of enabling ADC interface whenever
touchscreen is marked wakeup capable. Therefore, unconditionally disable
ADC interface during system suspend to save power in case of system with
just ADC and no TSC.

Signed-off-by: Vignesh R 
Acked-by: Jonathan Cameron 
Signed-off-by: Lee Jones

iio: adc: meson-saradc: use the address attribute from iio_chan_spec

2018-09-29T11:50:48+00:00

Until now the "channel" number is identical to how the channel is
identified inside the (FIFO) registers. In our case we have eight
channels and the hardware also has eight inputs.

However, there are two special inputs:
- channel 6 can select between the SAR_ADC_CH6 pad and the chip's
  internal temperature sensor
- channel 7 can select between SAR_ADC_CH7 and VSS, VDD / 4, VDD / 2,
  VDD * 3 / 4 and VDD.

When programming the registers to read for example the temperature
sensor we have to select FIFO channel 6, set the correct bit which muxes
channel 6 to the temperature sensor and then start the ADC measurement
for channel 6 as usual.

When we add support for the temperature sensor the driver has to know
about that it has to use FIFO channel 6 to measure using the chip's
internal temperature sensor. However, in that case the iio_chan_spec
channel will not be 6 because this is already used for the SAR_ADC_CH6
pad input. Thus we use iio_chan_spec's address field to store the FIFO
channel number for each channel.

Signed-off-by: Martin Blumenstingl 
Signed-off-by: Jonathan Cameron

iio: adc: meson-saradc: do not use meson_sar_adc_iio_channels directly

2018-09-29T11:48:22+00:00

In the future we may support two different channel sets:
- one which includes the voltage pads and the temperature sensor output
  (for Meson8, Meson8b and Meson8m2)
- one which only includes the voltage pads (GXBB, GXL, GXM and AXG)

Channel 7 has a special function on all of these platforms. However,
since we will have different channel array definitions we want our code
to always use whatever channels struct iio_dev uses.

No functional changes for now. This is the preparation for adding
temperature sensor support to this driver.

Signed-off-by: Martin Blumenstingl 
Signed-off-by: Jonathan Cameron

iio: adc: at91: fix wrong channel number in triggered buffer mode

2018-09-29T11:30:24+00:00

When channels are registered, the hardware channel number is not the
actual iio channel number.
This is because the driver is probed with a certain number of accessible
channels. Some pins are routed and some not, depending on the description of
the board in the DT.
Because of that, channels 0,1,2,3 can correspond to hardware channels
2,3,4,5 for example.
In the buffered triggered case, we need to do the translation accordingly.
Fixed the channel number to stop reading the wrong channel.

Fixes: 0e589d5fb ("ARM: AT91: IIO: Add AT91 ADC driver.")
Cc: Maxime Ripard 
Signed-off-by: Eugen Hristev 
Acked-by: Ludovic Desroches 
Cc: 
Signed-off-by: Jonathan Cameron

iio: adc: at91: fix acking DRDY irq on simple conversions

2018-09-29T11:30:19+00:00

When doing simple conversions, the driver did not acknowledge the DRDY irq.
If this irq status is not acked, it will be left pending, and as soon as a
trigger is enabled, the irq handler will be called, it doesn't know why
this status has occurred because no channel is pending, and then it will go
int a irq loop and board will hang.
To avoid this situation, read the LCDR after a raw conversion is done.

Fixes: 0e589d5fb ("ARM: AT91: IIO: Add AT91 ADC driver.")
Cc: Maxime Ripard 
Signed-off-by: Eugen Hristev 
Acked-by: Ludovic Desroches 
Cc: 
Signed-off-by: Jonathan Cameron

iio: adc: meson-saradc: simplify access to meson_sar_adc_param

2018-09-29T11:26:08+00:00

Commit 053ffe3c8cfe31 ("iio: adc: meson-saradc: squash and share the
common adc platform data") put all the data which is needed at runtime
from struct meson_sar_adc_data to a new struct meson_sar_adc_param so
we can re-use the platform specific configuration without having to
duplicate everything just to change the name.

The only place where struct meson_sar_adc_data is now needed is the
_probe function which has to pass the name to the iio_dev. All other
functions only need access to struct meson_sar_adc_param. This means we
can simplify struct meson_sar_adc_priv.

The goal of this patch is to make the code a bit easier to read since
this removes one level of nesting. No functional changes intended.

Signed-off-by: Martin Blumenstingl 
Signed-off-by: Jonathan Cameron

iio: adc: meson-saradc: use of_device_get_match_data

2018-09-29T11:26:08+00:00

This simplifies our _probe function by using of_device_get_match_data
instead of open-coding it. No functional changes.

Signed-off-by: Martin Blumenstingl 
Signed-off-by: Jonathan Cameron

iio: adc: meson-saradc: remove #define MESON_SAR_ADC_DELTA_10_TS_C_SHIFT

2018-09-29T11:26:07+00:00

This define is of no use because the driver is avoiding shifting bits
by itself but using FIELD_GET/FIELD_PREP (which are using bit masks)
instead. There is already a MESON_SAR_ADC_DELTA_10_TS_C_MASK bit mask so
MESON_SAR_ADC_DELTA_10_TS_C_SHIFT was redundant.

Signed-off-by: Martin Blumenstingl 
Signed-off-by: Jonathan Cameron

iio: adc: imx25-gcq: Fix leak of device_node in mx25_gcq_setup_cfgs()

2018-09-22T09:19:51+00:00

Leaving for_each_child_of_node loop we should release child device node,
if it is not stored for future use.

Found by Linux Driver Verification project (linuxtesting.org).

JC: I'm not sending this as a quick fix as it's been wrong for years,
but good to pick up for stable after the merge window.

Signed-off-by: Alexey Khoroshilov 
Fixes: 6df2e98c3ea56 ("iio: adc: Add imx25-gcq ADC driver")
Cc: 
Signed-off-by: Jonathan Cameron